A non-interfering cognitive radio system for spectrum sharing
Yangsoo Kwon, Hyeonsu Kim, Jae-Ho Yoo, Jaehak Chung · 2009
We present a cognitive radio beamformer for spectrum sharing with primary users. The proposed method generates orthogonal multiple beams for cognitive users using orthogonal subspaces and opportunistic beamforming methods to increase the sum-rate of cognitive radio systems. Simulations demonstrate that the proposed scheme does not cause interference for the primary users and provides a sum-rate capacity of 2.72bps/Hz for up to 20 cognitive users with two transmit antennas.